Search results
Results from the WOW.Com Content Network
E. F. Codd mentioned nulls as a method of representing missing data in the relational model in a 1975 paper in the FDT Bulletin of ACM-SIGMOD.Codd's paper that is most commonly cited with the semantics of Null (as adopted in SQL) is his 1979 paper in the ACM Transactions on Database Systems, in which he also introduced his Relational Model/Tasmania, although much of the other proposals from ...
MySQL (/ ˌ m aɪ ˌ ɛ s ˌ k juː ˈ ɛ l /) [6] is an open-source relational database management system (RDBMS). [6] [7] Its name is a combination of "My", the name of co-founder Michael Widenius's daughter My, [1] and "SQL", the acronym for Structured Query Language.
The MySQL GUI Tools Bundle is a cross-platform open source suite of desktop applications for the administration of MySQL database servers, and for building and manipulating the data within MySQL databases. It was developed by MySQL AB and later by Sun Microsystems and released under the GPL.
TIBCO Spotfire does not support CTEs, while Oracle 11g Release 2's implementation lacks fixpoint semantics. Without common table expressions or connected-by clauses it is possible to achieve hierarchical queries with user-defined recursive functions. [7]
Yes - user manager with support for database and schema permissions as well as for individual object (table, view, functions) permissions; Some - simple user manager with support for database and schema permissions; No - no user manager, or read-only user manager
Just as a function (in programming) can provide abstraction, so can a database view. In another parallel with functions, database users can manipulate nested views, thus one view can aggregate data from other views. Without the use of views, the normalization of databases above second normal form would become much more difficult. Views can make ...
HAVING and WHERE are often confused by beginners, but they serve different purposes.WHERE is taken into account at an earlier stage of a query execution, filtering the rows read from the tables.
A database trigger is procedural code that is automatically executed in response to certain events on a particular table or view in a database. The trigger is mostly used for maintaining the integrity of the information on the database. For example, when a new record (representing a new worker) is added to the employees table, new records ...